docs: def invalidate(self, assoc_handle, dumb):
          """Invalidates the association with the given handle.
  
          @type assoc_handle: str
  
          @param dumb: Is this association used with dumb mode?
          @type dumb: bool
          """
          if dumb:
              key = self._dumb_key
          else:
              key = self._normal_key
          self.store.removeAssociation(key, assoc_handle)